Relay Optocoupler High Low Level Trigger 1 2 4 8 Channel 5 12 24V Module Arduino

High Low Level Trigger 1-2-4-8 Channel Relay Optocoupler 5 12 24V Module Arduino PI. High and low level trigger Connection low level trigger when jumper connects to LOW pin(L). high level trigger when jumper connects to HIGH pin(H).

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